The Grace Instrument M9100 Automatic Core Flow Tester is designed to accurately measure permeability changes to a formation core sample in a high temperature and high pressure environment, while exposing it to a variety of test fluids. A core that is collected from a formation is inserted into a core holder. A computer with Grace Instrument M9100 Core Flow™ software controls the environment within the core holder and the injection rate and/or pressure of fluid into the core. Many different types of tests can be performed with the M9100 by changing the test parameters in the test setup section of the M9100 Core Flow™ software.